The invention relates to apparatus for operating a closure, a material handling system including such apparatus, and a method of transferring a flowable material from a material storage container.
Material handling apparatus generally consists of a storage container or silo, with a discharge aperture, and operating means therefor. Product from the silo is discharged mainly due to gravity through the aperture which is generally located at or near the bottom of the apparatus. A problem experienced with apparatus such as this is that on delivery, brittle, or friable products such as for example, tablets, can be damaged. In particular, when the aperture is closed after an amount of product has been dispensed, product trapped between the closure and the rim of the aperture may be crushed, resulting in a loss of useable product, and potential contamination by dust.
It is an object of the invention to mitigate problems such as this.
According to the invention there is provided apparatus for operating a closure for an aperture of a material storage container, comprising means to regulate the position of the closing relative to the aperture during closure thereof.
The regulating means may comprise moveable stop means adapted to abut a part of the apparatus when the closure is moved toward the closed position.
The regulating means may include adjustment means to adjust the position of the stop means relative to the closure.
The adjustment means may be operable to move the stop means from an operating to a non-operating position.
The stop means may be pivotably mounted for movement between the operating and non-operating positions.
The adjustment means may comprise cylinder means.
The stop means may comprise a tapering nose part, a surface of which is disposed to contact a part of the apparatus when the closure is moved toward the closed position.
The apparatus may comprise cylinder means for operating the closure.
It is preferred that the regulating means is adapted to cooperate with a part of the cylinder means for regulation of the position of the closure. The cylinder part may comprise an elongate extension, which moves with the cylinder means when it is operated.
According to a second aspect of the invention, there is provided a material handling system including a material storage container having an aperture and a closure therefor, comprising apparatus as hereinbefore defined. The apparatus is preferably disposed outside of the container and closure.
According to a third aspect of the invention there is provided a method of transferring a flowable product from a material storage container which comprises the steps of providing apparatus to open a closure of the container, allowing material to run out of the container and then operating the apparatus to move the closure toward a closed position to leave a gap between the closure and the container, so that material trapped between the closure and the container is not crushed.